/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Ben Goodger <ben@netscape.com> (Original Author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
////////////////////////////////////////////////////////////////////////////
// XXX - WARNING - DRAG AND DROP API CHANGE ALERT - XXX
// This file has been extensively modified in a checkin planned for Mozilla
// 0.8, and the API has been modified. DO NOT MODIFY THIS FILE without
// approval from ben@netscape.com, otherwise your changes will be lost.
/**
* nsTransferable - a wrapper for nsITransferable that simplifies
* javascript clipboard and drag&drop. for use in
* these situations you should use the nsClipboard
* and nsDragAndDrop wrappers for more convenience
**/
var nsTransferable = {
/**
* nsITransferable set (TransferData aTransferData) ;
*
* Creates a transferable with data for a list of supported types ("flavours")
*
* @param TransferData aTransferData
* a javascript object in the format described above
**/
set: function (aTransferDataSet)
{
var trans = this.createTransferable();
for (var i = 0; i < aTransferDataSet.dataList.length; ++i)
{
var currData = aTransferDataSet.dataList[i];
var currFlavour = currData.flavour.contentType;
trans.addDataFlavor(currFlavour);
var supports = null; // nsISupports data
var length = 0;
if (currData.flavour.dataIIDKey == "nsISupportsString")
{
supports = Components.classes["@mozilla.org/supports-string;1"]
.createInstance(Components.interfaces.nsISupportsString);
supports.data = currData.supports;
length = supports.data.length;
}
else
{
// non-string data.
supports = currData.supports;
length = 0; // kFlavorHasDataProvider
}
trans.setTransferData(currFlavour, supports, length * 2);
}
return trans;
},
/**
* TransferData/TransferDataSet get (FlavourSet aFlavourSet,
* Function aRetrievalFunc, Boolean aAnyFlag) ;
*
* Retrieves data from the transferable provided in aRetrievalFunc, formatted
* for more convenient access.
*
* @param FlavourSet aFlavourSet
* a FlavourSet object that contains a list of supported flavours.
* @param Function aRetrievalFunc
* a reference to a function that returns a nsISupportsArray of nsITransferables
* for each item from the specified source (clipboard/drag&drop etc)
* @param Boolean aAnyFlag
* a flag specifying whether or not a specific flavour is requested. If false,
* data of the type of the first flavour in the flavourlist parameter is returned,
* otherwise the best flavour supported will be returned.
**/
get: function (aFlavourSet, aRetrievalFunc, aAnyFlag)
{
if (!aRetrievalFunc)
throw "No data retrieval handler provided!";
var supportsArray = aRetrievalFunc(aFlavourSet);
var dataArray = [];
var count = supportsArray.Count();
// Iterate over the number of items returned from aRetrievalFunc. For
// clipboard operations, this is 1, for drag and drop (where multiple
// items may have been dragged) this could be >1.
for (var i = 0; i < count; i++)
{
var trans = supportsArray.GetElementAt(i);
if (!trans) continue;
trans = trans.QueryInterface(Components.interfaces.nsITransferable);
var data = { };
var length = { };
var currData = null;
if (aAnyFlag)
{
var flavour = { };
trans.getAnyTransferData(flavour, data, length);
if (data && flavour)
{
var selectedFlavour = aFlavourSet.flavourTable[flavour.value];
if (selectedFlavour)
dataArray[i] = FlavourToXfer(data.value, length.value, selectedFlavour);
}
}
else
{
var firstFlavour = aFlavourSet.flavours[0];
trans.getTransferData(firstFlavour, data, length);
if (data && firstFlavour)
dataArray[i] = FlavourToXfer(data.value, length.value, firstFlavour);
}
}
return new TransferDataSet(dataArray);
},
/**
* nsITransferable createTransferable (void) ;
*
* Creates and returns a transferable object.
**/
createTransferable: function ()
{
const kXferableContractID = "@mozilla.org/widget/transferable;1";
const kXferableIID = Components.interfaces.nsITransferable;
return Components.classes[kXferableContractID].createInstance(kXferableIID);
}
};
/**
* A FlavourSet is a simple type that represents a collection of Flavour objects.
* FlavourSet is constructed from an array of Flavours, and stores this list as
* an array and a hashtable. The rationale for the dual storage is as follows:
*
* Array: Ordering is important when adding data flavours to a transferable.
* Flavours added first are deemed to be 'preferred' by the client.
* Hash: Convenient lookup of flavour data using the content type (MIME type)
* of data as a key.
*/
function FlavourSet(aFlavourList)
{
this.flavours = aFlavourList || [];
this.flavourTable = { };
this._XferID = "FlavourSet";
for (var i = 0; i < this.flavours.length; ++i)
this.flavourTable[this.flavours[i].contentType] = this.flavours[i];
}
FlavourSet.prototype = {
appendFlavour: function (aFlavour, aFlavourIIDKey)
{
var flavour = new Flavour (aFlavour, aFlavourIIDKey);
this.flavours.push(flavour);
this.flavourTable[flavour.contentType] = flavour;
}
};
/**
* A Flavour is a simple type that represents a data type that can be handled.
* It takes a content type (MIME type) which is used when storing data on the
* system clipboard/drag and drop, and an IIDKey (string interface name
* which is used to QI data to an appropriate form. The default interface is
* assumed to be wide-string.
*/
function Flavour(aContentType, aDataIIDKey)
{
this.contentType = aContentType;
this.dataIIDKey = aDataIIDKey || "nsISupportsString";
this._XferID = "Flavour";
}
function TransferDataBase() {}
TransferDataBase.prototype = {
push: function (aItems)
{
this.dataList.push(aItems);
},
get first ()
{
return "dataList" in this && this.dataList.length ? this.dataList[0] : null;
}
};
/**
* TransferDataSet is a list (array) of TransferData objects, which represents
* data dragged from one or more elements.
*/
function TransferDataSet(aTransferDataList)
{
this.dataList = aTransferDataList || [];
this._XferID = "TransferDataSet";
}
TransferDataSet.prototype = TransferDataBase.prototype;
/**
* TransferData is a list (array) of FlavourData for all the applicable content
* types associated with a drag from a single item.
*/
function TransferData(aFlavourDataList)
{
this.dataList = aFlavourDataList || [];
this._XferID = "TransferData";
}
TransferData.prototype = {
__proto__: TransferDataBase.prototype,
addDataForFlavour: function (aFlavourString, aData, aLength, aDataIIDKey)
{
this.dataList.push(new FlavourData(aData, aLength,
new Flavour(aFlavourString, aDataIIDKey)));
}
};
/**
* FlavourData is a type that represents data retrieved from the system
* clipboard or drag and drop. It is constructed internally by the Transferable
* using the raw (nsISupports) data from the clipboard, the length of the data,
* and an object of type Flavour representing the type. Clients implementing
* IDragDropObserver receive an object of this type in their implementation of
* onDrop. They access the 'data' property to retrieve data, which is either data
* QI'ed to a usable form, or unicode string.
*/
function FlavourData(aData, aLength, aFlavour)
{
this.supports = aData;
this.contentLength = aLength;
this.flavour = aFlavour || null;
this._XferID = "FlavourData";
}
FlavourData.prototype = {
get data ()
{
if (this.flavour &&
this.flavour.dataIIDKey != "nsISupportsString" )
return this.supports.QueryInterface(Components.interfaces[this.flavour.dataIIDKey]);
else {
var unicode = this.supports.QueryInterface(Components.interfaces.nsISupportsString);
if (unicode)
return unicode.data.substring(0, this.contentLength/2);
return this.supports;
}
return "";
}
}
/**
* Create a TransferData object with a single FlavourData entry. Used when
* unwrapping data of a specific flavour from the drag service.
*/
function FlavourToXfer(aData, aLength, aFlavour)
{
return new TransferData([new FlavourData(aData, aLength, aFlavour)]);
}
var transferUtils = {
retrieveURLFromData: function (aData, flavour)
{
switch (flavour) {
case "text/unicode":
return aData;
case "text/x-moz-url":
return aData.toString().split("\n")[0];
case "application/x-moz-file":
var ioService = Components.classes["@mozilla.org/network/io-service;1"]
.getService(Components.interfaces.nsIIOService);
var fileHandler = ioService.getProtocolHandler("file")
.QueryInterface(Components.interfaces.nsIFileProtocolHandler);
return fileHandler.getURLSpecFromFile(aData);
}
return null;
}
}
/*
function DUMP_obj (aObj)
{
for (var i in aObj)
dump("*** aObj[" + i + "] = " + aObj[i] + "\n");
}
*/